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From: Bob Proulx on 15 Jul 2010 18:19
Intransition wrote:
> Any advice on how a ruby script can set a config info that's per
> parent process.

Using an environment variable?

> In other words I want to be able to do something like:
> ...
> But if I close my terminal and/or open a new terminal then it will
> have it's own setting.

Have foo set an environment variable and then exec a new shell. The
foo script later can print the variable if it exists. Here is
something off the top of my head. Untested. It spawns a new shell
though and that may be too disruptive for your needs.

Bob


#!/bin/sh
if [ -n "$myuniquefoovar" ]; then
echo "$myuniquefoovar" # or possibly printf
exit 0
fi
if [ $# -ne 0 ]; then
myuniquefoovar="$*"
export myuniquefoovar
exec $SHELL
fi
exit 0

From: Intransition on 15 Jul 2010 20:10
On Jul 15, 6:19 pm, Bob Proulx <b...(a)proulx.com> wrote:

> Have foo set an environment variable and then exec a new shell.  The
> foo script later can print the variable if it exists.  Here is
> something off the top of my head.  Untested.  It spawns a new shell
> though and that may be too disruptive for your needs.
>
> Bob
>
> #!/bin/sh
> if [ -n "$myuniquefoovar" ]; then
>   echo "$myuniquefoovar" # or possibly printf
>   exit 0
> fi
> if [ $# -ne 0 ]; then
>   myuniquefoovar="$*"
>   export myuniquefoovar
>   exec $SHELL
> fi
> exit 0

Thanks, I feel like I've gotten a step closer, but still no cigar. I
was able to get the child shell, which is cool --and I can accept that
if need to be o get this to work. But I can't get the environment
variable transfer into the new shell.


From: Intransition on 15 Jul 2010 20:27
On Jul 15, 8:10 pm, Intransition <transf...(a)gmail.com> wrote:
> > #!/bin/sh
> > if [ -n "$myuniquefoovar" ]; then
> >   echo "$myuniquefoovar" # or possibly printf
> >   exit 0
> > fi
> > if [ $# -ne 0 ]; then
> >   myuniquefoovar="$*"
> >   export myuniquefoovar
> >   exec $SHELL
> > fi
> > exit 0
>
> Thanks, I feel like I've gotten a step closer, but still no cigar. I
> was able to get the child shell, which is cool --and I can accept that
> if need to be o get this to work. But I can't get the environment
> variable transfer into the new shell.

Just discovered that capitalized variables (environment variables) are
not transferred. But lowercase variables (shell variables) are.

So this will work! Thanks Bob.

From: Phil Romero on 15 Jul 2010 20:45
On Thu, Jul 15, 2010 at 2:35 PM, Intransition <transfire(a)gmail.com> wrote:
> Any advice on how a ruby script can set a config info that's per
> parent process. In other words I want to be able to do something like:
>
>  $ foo
>  no setting
>
> Then...
>
>  $ foo 10
>
> Which will store 10 somehow. And when I run foo again it can output
> 10.
>
>  $ foo
>  10
>
> But if I close my terminal and/or open a new terminal then it will
> have it's own setting.
>
>  % foo
>  no setting
>
> Thanks.
>
>

$ env FOO="something" sh
$ echo "${FOO}"
something
$ exit
$ echo "${FOO}"

$ env FOO="string for ruby to print" ruby -e 'puts ENV["FOO"]'
string for ruby to print
$ echo "${FOO}"

$

From: Intransition on 15 Jul 2010 23:25

On Jul 15, 8:27 pm, Intransition <transf...(a)gmail.com> wrote:

> Just discovered that capitalized variables (environment variables) are
> not transferred. But lowercase variables (shell variables) are.

Looks like I am wrong about this. I ran an isolated test and they both
come through --not sure why my capitalized form was getting clobbered.


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